The present invention is directed to an improvement in a bidirectional optical transmission and reception arrangement which includes an optical transmitter having a transmitter window for the emission of an optical radiation having a first wavelength, an optical receiver having a receiver window for the reception of an optical radiation having a second wavelength, an optical delivery arrangement for delivering the radiation having the first wavelength emitting from the transmitter window to a predetermined spatial point at a distance from the transmitter window and from the receiver window and for delivering the radiation having the second wavelength emitting from the spatial point to the receiver window, and an optical shielding arrangement for shielding the receiver window against the radiation having the first wavelength and for shielding the transmitter window against the radiation having the second wavelength.
A known bidirectional optical transmission and reception arrangement has an optical transmitter, which is a laser diode, and an optical receiver, which is a photodiode with a photodiode window. The optical delivery arrangement for the arrangement comprises two optical lenses. One of the lenses is for optically imaging a laser beam of the first wavelength emitting from the laser diode window on a specific spatial point at a distance from the laser window and the photodiode window and the other lens is for the optical imaging of the second wavelength emitting from the spatial point onto the photodiode window. The arrangement includes optical shielding means which is composed of a separate, wavelength-selective optical filter arranged obliquely in the beam path of the radiations of the two wavelengths, and this optical filter is non-transmissive for one of the two wavelengths and is only transmissive for the other of the two wavelengths.